The present invention relates to a pattern defect detection apparatus using a scanning and transmission electron microscope optimum for inspecting a circuit pattern or the like formed on a mask to fabricate semiconductor devices or the like and in particular for inspecting a circuit pattern of a mask used for X-ray lithography.
Scanning and transmission electron microscopes (STEM) of the prior art are described in No. JP-A-55-151757 and "Microbeam Analysis" written by the 141-th committee (Microbeam Analysis) of Japan Association for Advancement of Science and Technology and published by Asakura Bookstore on June 1, 1985, pp. 199 to 206, for example.
In these STEMs of the prior art, however, defects of the circuit pattern of an X-ray mask or the like having a comparatively large size could not be detected accurately.